Have you ever noticed the no cell phone signs at the gas station and wondered why you’re not supposed to use your phone at the gas station?
Initially, cell phone makers feared sparks created by the small motor in a cell phone could ignite fumes. This has never happened, and in modern cell phones, this is considered highly unlikely if not impossible. So today, the rule is based on reducing distractions while handling flammable chemicals.
A much more dangerous phenomenon at the gas station is static electricity. There have been fires at gas stations due to a static discharge while fueling that ignited the fumes.
What is the real reason you’re not supposed to use a cell phone while fueling?
The biggest concern is that the cell phone is a distraction, gasoline and its fumes are highly flammable, and static electricity can be present in the area.
When you’re pumping fuel, you don’t want any distractions. The equipment for transferring fuel has been made exceptionally safe, but trouble can happen. For example, if the nozzle falls out of the receiver on your vehicle, it can spray a lot of fuel before someone can shut it off.
This could happen if the nozzle doesn’t seat correctly or if you or your passengers are getting in and out of the vehicle while fueling.
There is a safety mechanism in the nozzle in all modern fuel pumps that shuts off the flow when fuel splashes back onto it. But what if it falls in such a way that it never splashes back on the sensor? I’ve had this happen to me when I worked at a fuel station in my late teens.
Getting fuel on yourself is not healthy. It isn’t good for your skin and all your soft tissues. You also really don’t want to ingest it. All of this before we consider that you have a highly flammable chemical on you in an area known for static electricity.
As mentioned, the primary concern at a fuel station is static electricity. That’s because the spark generated by static electricity is enough to ignite gas fumes. Unfortunately, it’s something that has happened in the past with tragic results.
Where do we find static electricity at the gas station?
There are several known places where people can have static electricity when at the fuel station:
- On your body
- On other people around you
- On the body of your vehicle
- Generated as fuel is transferred
Fuel station pumps are designed to be grounded so that the static electricity generated by transferring fuel can’t build up and cause problems.
However, you must follow correct procedures while fueling to make sure you aren’t circumventing them. For example, when you fuel portable containers, you want to set them on the ground to fill them. Never fill a portable container while it’s in your vehicle.
How does static electricity build up at the gas station?
If the weather is dry and your clothing is prone to static build-up, it can build up on your body just by getting in and out of your vehicle. The same goes for if you have long hair in dry weather. If you notice that you have a lot of static on you when you’re getting out of your vehicle, make sure you discharge it in a safe place before you begin fueling.
Your vehicle is insulated from the ground by the tires. As a result, you can also generate a static charge on the vehicle body when you slide in and out of your seat. My truck seats are bad for this. So when you get out and place a foot on the ground, you can get a pretty big shock as soon as you touch the body.
The way around this is to touch a metallic part of the body as you exit the vehicle before your foot touches the ground. This gives the electricity a path to travel without jumping and creating a spark.
The fuel itself generates another significant source of static electricity whenever you transfer fuel. As the fuel travels through hoses and other lines, it rubs against all of those surfaces and can create a dangerous electric charge right where you don’t want it.
The way pump manufacturers have corrected this is to ground the lines, so the charge doesn’t have a chance to build up. This works great when the metal nozzle sits in the metal receiver on your vehicle. The problem arises when customers pumping fuel circumvent these protections. Unfortunately, it’s easier to do than you think.
Modern portable fuel containers are primarily made of plastic. If you transfer fuel into a portable plastic container while it sits on your vehicle, the container is insulated from the ground by your tires and is exposed to flowing fuel.
This can be a dangerous combination where a static charge can build up on the container in the presence of gasoline fumes and a direct connection to ground through the fuel nozzle.
The solution to this is to fill all portable containers as they sit on the ground. Contact with the earth should mitigate any risk of static charge since the charge should reach ground before building up to dangerous levels.
Why should you not enter and exit your vehicle while fueling?
As mentioned above, when you get in and out of your vehicle, your clothing rubs on the seat and can generate an enormous amount of charge on your body and the body of the car. Doing this while you are fueling can be very dangerous.
You’re essentially taking the chance of creating a spark between you and a fueling vehicle during the ideal time for fuel fumes to be present. And that’s presuming the spark occurs in the area around the vehicle door. Before your foot touches the ground, the most convenient path for static electricity to travel through is the fuel nozzle sitting in your vehicle.
That’s the absolute worst place for a spark to occur. It may be cold outside, or you may want to sit while you wait, but it isn’t worth taking the risk, especially if it’s so that you have a cozy place to use your phone.